PT - JOURNAL ARTICLE AU - Meng Lee AU - Jeffrey L. Saver AU - Keun-Sik Hong AU - Yi-Ling Wu AU - Hsing-Cheng Liu AU - Neal M. Rao AU - Bruce Ovbiagele TI - Cognitive impairment and risk of future stroke: a systematic review and meta-analysis AID - 10.1503/cmaj.140147 DP - 2014 Oct 07 TA - Canadian Medical Association Journal PG - E536--E546 VI - 186 IP - 14 4099 - http://www.cmaj.ca/content/186/14/E536.short 4100 - http://www.cmaj.ca/content/186/14/E536.full SO - CMAJ2014 Oct 07; 186 AB - Background: Several studies have assessed the link between cognitive impairment and risk of future stroke, but results have been inconsistent. We conducted a systematic review and meta-analysis of cohort studies to determine the association between cognitive impairment and risk of future stroke.Methods: We searched MEDLINE and Embase (1966 to November 2013) and conducted a manual search of bibliographies of relevant retrieved articles and reviews. We included cohort studies that reported multivariable adjusted relative risks and 95% confidence intervals or standard errors for stroke with respect to baseline cognitive impairment.Results: We identified 18 cohort studies (total 121 879 participants) and 7799 stroke events. Pooled analysis of results from all studies showed that stroke risk increased among patients with cognitive impairment at baseline (relative risk [RR] 1.39, 95% confidence interval [CI] 1.24–1.56). The results were similar when we restricted the analysis to studies that used a widely adopted definition of cognitive impairment (i.e., Mini-Mental State Examination score < 25 or nearest equivalent) (RR 1.64, 95% CI 1.46–1.84). Cognitive impairment at baseline was also associated with an increased risk of fatal stroke (RR 1.68, 95% CI 1.21–2.33) and ischemic stroke (RR 1.65, 95% CI 1.41–1.93).Interpretation: Baseline cognitive impairment was associated with a significantly higher risk of future stroke, especially ischemic and fatal stroke.